This is known as an accordion menu. Here is a tutorial on how to create one using jQuery.
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                  Andrew Hare
                   2009-10-20 23:47:28
                
              
                
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            This is an Accordion Menu and is available as a widget in Jquery UI - http://docs.jquery.com/UI/Accordion
                  Alex Sexton
                   2009-10-20 23:48:37
                
              
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            This is accordion menu.
jQuery docs here:
http://docs.jquery.com/UI/Accordion
http://plugins.jquery.com/project/accordion
                  Michal M
                   2009-10-20 23:48:49
                
              
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              I'm sure you know, by now, that this is the accordion menu style, I'll just suggest -if you're amenable to a non-jQuery option- that you visit Stu Nicholl's css-play website, where he has a pure xhtml/css version of this accordion menu style.
                  David Thomas
                   2009-10-20 23:51:52
                
              Wow, that's actually pretty cool for not using a single line of script!
                  Gurdas Nijor
                   2009-10-20 23:55:44
                Thanks for the link! I found exactly what I wanted.
                  Nescio
                   2009-10-21 00:11:44
                @Gurdas, I've found Stu Nicholl's site to be indispensable over the years for learning new things and dealing with CSS problems. His css games, though, are *pure* awesome: http://www.cssplay.co.uk/menu/ (under the heading 'Puzzles') =)
                  David Thomas
                   2009-10-21 00:34:53
                
                
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            This is known as the Accordian Menu UI pattern. There are quite a few jQuery plugin implementations, including this one: jQuery Accordion.
More info and some good examples here:
                  cxfx
                   2009-10-20 23:56:20